1. Technical Field
The present invention relates to a printer having a platen that is freely detachably mounted in a printer frame, and particularly to a printer in which a platen installed in a cover is detachably mounted in a printer frame in connection with opening/closing of the cover in a drop-in type printer in which a cover is freely openable/closable with respect to the printer main body.
2. Background Art
A printer disclosed in Patent Document 1 which has been proposed by the applicant of this application is known as this type of printer. According to the printer disclosed in the Patent Document 1, a platen held in a platen holder is configured to be freely detachably mounted in a frame for holding a print head. As shown in FIG. 11 of the Patent Document 1, the platen holder is installed in a platen unit arm (corresponding to a cover), and the frame is installed in a platen unit base (corresponding to a printer main body).
A support groove in/from which the rotational shaft of the platen is inserted/detached in connection with attachment/detachment of the platen is formed in the frame. A platen-side gear is secured to one end of the rotational shaft of the platen, and a driving motor and a rotational driving mechanism are installed in the frame so that the rotational driving force of the driving motor is transmitted to the platen-side gear through the rotational driving mechanism.
The rotational driving mechanism is constructed by a gear train with which the rotational driving force is transmitted through the engagement of plural gears, and one gear located at the most downstream side (hereinafter referred to as a driving-side engaging gear) is engaged with the platen-side gear.    Patent Document 1: JP-A-2003-246103